1) Field of the Invention
The present invention relates to a modified pistol upper employing a novel muzzle device that allows for using standard length rifle handguards with the pistol upper.
2) Description of Related Art
Current AR-15 platforms use a shoulder machined into the barrel to position the front sight base and hand guard retainer on the barrel to the correct length. Pins are typically drilled into the barrel to hold it into place. See FIG. 1. Due to this configuration, a barrel shorter than 8.75 inches is not long enough to hold a standard front sight base and carbine length handguard in place, most pistol upper assemblies use a free-floating hand guard. This allows the barrel to free float and will not accommodate the use of a standard polymer handguard. FIG. 2 shows an example of a free float pistol upper.
Accordingly, it is an object of the present invention to improve over past pistol upper designs to allow a user to employ a standard carbine length handguard retainer on a pistol upper assembly.